Neuro Drugs Flashcards
Vestibular neuronitis vs. labyrinthitis
Both are an inflammation in the inner ear
Vestibular neuronitis = continuuous vertigo w/o hearing loss
- often after a URI
- self-limited viral infection of the vestibular division of the vestibulocochlear nerve
Labyrinthitis = Combo of vestibular neuritis plus hearing symptoms
-often spread of infxn from the middle ear
3 ddx for restricted diffusion area on DWI scan
- infarct
- failure of Na/K pump traps water in cells - Abscess
- water poorly diffuses thru pus - Hypercellular tumors
- primary CNS lymphomas
- medulloblastoma (children)
COMT inhibitors
COMT inhibitors block the enzyme that breaks down excess dopamine at the presynaptic neuron => increases half life of sinemet
What is the caloric reflex testing?
(a) Normal response?
Caloric reflex testing: to test the vestibular-ocular reflex
(a) Normal response: COWS = cold-opposite, warm-same
- cold water causes fast beat of nystagmus to the side opposite the ear where cold water is entered
- warm water causes fast beat of nystagmus to the same side of the ear where warm water is placed
35 yo M develops sudden twisting of neck and protruding tongue after presenting to the ER w/ terrible nausea 2/2 migraine
(a) What med was he given?
(b) Tx
(a) Metoclopramide/Reglan
- antiemetics can cause drug-induced Parkinsonism
(b) Tx - diphenhydramine (benadryl)
Guanfacine
(a) Mechanism
(b) Major indications
Guanfacine (Tenex)
(a) Selective alpha-2A agonist = sympatholytic
(b) ADHD, tics, GAD, HTN
Essential tremor
(a) Symptoms commonly alleviated by what?
(b) First line tx
Essential tremor
(a) Often alleviated by EtOH
(b) First line tx = non-selective beta-blocker = Propranolol
- selective (like atenolol) not as effective b/c beta-1 effects predominate
Function of the vestibular-ocular reflex
VOR = keep eyes fixated on object when head is moved rapidly
Tx for orthostatic hypotension in Parkinson’s pt
Tx w/ fludrocortisone = synthetic corticosteroid w/ moderate glucocorticoid but very potent mineralocorticoid effect
=> acts like aldo to cause salt (and therefore water) retention
What does a positive Romberg’s test indicate?
Positive Romberg’s = pt steady when eyes are open, but loses balances when closes eyes, indicates instability of the proprioceptive system
Indicates vestibulopathy (injury to the vestibular system)
Most common culprits of drug-induced Parkinson’s
Typical antipsychotics and anti-emetics (reglan)
Also CCB
Pt on triptans as abortive med for migraine w/ aura wants contraception, best advice?
Estrogen-containing contraception (combined OCPs) contraindicated in ppl w/ migraine w/ aura b/c f the increased stroke risk
So:
- mini pill (progesterone only)
- IUD
Tx of Tourette’s
(a) First line
(b) Second line
Tourette’s
(a) First line = guanfacine (Tenex) = sympatholytic = selective alpha-2A agonist
(b) Can also use haldol/risperdal
Name some central causes of vertigo
Central causes of vertigo
- ischemic and hemorrhage stroke
- MS
- vertebral artery dissection
- migraine
Natalizumab (Tysabri)
(a) Mechanism
(b) Side effects
Natalizumab (Tysabri)
(a) Interferes w/ receptor to reduce transmission of immune cells into the CNS
(b) Major concern = risk of PML
(a) First line tx for restless leg syndrome
(b) What can RLS be a predecessor of?
(a) Dopamine agonists
ex: roperinole
(b) Often precedes more serious illness like Parkinson’s
Tx for spastic torticollis
Tx = botulinum toxin
Define vertigo
(a) Symptoms of acute vertigo syndrome
Vertigo = abnormal sensation of movement due to asymmetric neural activity from the right and left vestibular systems
(b) N/V, nystagus, postural instability
Central causes of vertigo associated w/
(a) multiple prodromal episodes of dizziness
(b) HA and neck pain
(c) Truncal ataxia and gait instability
Central causes of vertigo (obv more concerning than peripheral)
(a) TIA
(b) HA, neck pain, vertigo- c/f vertebral artery dissection
(c) Cerebellar infarct
Contraindication to sumatriptan use as abortive med for migraine HA
Coronary artery disease b/c triptans have vasoconstrictive properties and therefore carry risk of stroke
Pt on haloperidol develops fever and rigidity
Tx?
Tx = dopamine agonists = Bromocriptine
(a) When are meds for migraine ppx indicated?
(b) Meds for migraine ppx
(a) Meds indicated when pt has 2 or more migraines in a month, also if the migraines disrupt school/work
(b) Most common = Topiramate (AED)
Can also use: AED (Depakote), TCAs (amitriptiline), beta-blocker (propranolol), riboflavin (B2), and CCB
Differentiate central and peripheral nystagmus
(a) Direction
(b) Effect of change in direction
(c) Effect of visual fixation
(d) Presence of brainstem symptoms or hearing loss
(e) Direction of truncal instability
(f) Severity of symptoms
Central nystagmus (CNS pathology)
(a) Vertical or rotary
(b) May change w/ direction of gaze
(c) Symptoms unchanged by visual fixation (staring at something)
(d) May be presence of brainstem symptoms (diplopia, weakness, numbness, ataxia) but no hearing loss
(e) Pt falls towards the side of the lesion
(f) Mild vertigo
Peripheral nystagmus
(a) Usually horizontal, occasionally rotary (but not vertical)
(b) Unidirectional and conjugate = same direction and same in both eyes
(c) Decreased nystagmus (and vertigo) w/ visual fixation in peripheral
(d) No brainstem/neurologic findings, may be hearing loss
(e) Pt falls away from the lesion
(f) Severe vertigo, prominent N/V
First line for tx of chorea in Huntington’s
High potency typical antipsychotic, usually Haloperidol
